Recently, as a water-reducing agent which improves the consistency of cement compositions and which decreases the change in fluidity such as slump loss with the lapse of time, a condensation product with high-molecular weight used aromatic aminosulfonic acids and phenols has been developed (Japanese Unexamined Patent Publication No. Hei 1-113419).
In this reaction, however, unreacted aromatic aminosulfonic acid showing no water-reducing property (dispersibility) ends up to remain in large amounts. This is considered to be due to the fact that phenols tend to make homopolymer. In addition, because of this property of phenols, the stability under acidic condition etc. cannot be said to be good.
In the invention, a condensate is provided, which has aromatic aminosulfonic acid as a component, in which unreacted aromatic aminosulfonic acid being an ineffective component is decreased to the utmost and yet which has more excellent performance and is useful in wider scope of fields over conventional aromatic aminosulfinic acid type condensate by imparting polar group, heat-resistant structure and stericity to the hydrophobic skeleton.
Next, the disperse dye has been mainly used so far for dyeing polyester fibers etc. This is made up to be dispersed stably into water by using dispersing agent, since the dye itself of disperse dye is insoluble or hard soluble into water.
As dispersing agents in such case, lignin sulfonic acid, naphthalenesulfonic acid-formaldehyde condensate, etc. have been used.
Lignin sulfonic acid is excellent in dispersibility at high temperature and exhibits good dispersibility even in a high-temperature region such as the case of dyeing polyester fibers. On the other hand, however, it tends to contaminate the cloths.
Moreover, with naphthalenesulfonic acid-formaldehyde condensate, the contaminability is low in an ordinary temperature region and it is excellent in this respect. But, it has a problem on the high-temperature dispersibility, thus the dispersibility decreases to the utmost in a high-temperature region.
Besides these lignin sulfonic acid and naphthalenesulfonic acid-formaldehyde condensate, a condensation product comprising cresol, 2-hydroxynaphthalene, sulfite and formaldehyde (Japanese Unexamined Patent Publication No. Sho 54-30983) etc. have been developed, but they are insufficient in any of high-temperature dispersibility, contaminability and leveling property.
As a result of diligent investigations on the dye dispersion which exhibits excellent dispersibility even in a high-temperature region, less contaminability and excellent leveling property, the inventors have reached the invention.
Next, accompanying with the worsening circumstances of oil supply, the coal, which is abundant in resources, lies in wide deposit areas and distributes over all parts of the world, has been reconsidered as an energy source in substitution for oil.
Moreover, the petroleum coke being a distillation residue of oil, which found little utilization hitherto as an energy source, has also become to attract attention as an important energy source.
However, the carbonaceous fine powder of coal, petroleum coke, etc. is solid material as opposed to oil making it impossible to transport by pump. For this reason, a method of pulverizing coal and petroleum coke, dispersing them into water and converting to water slurry has been put into practice.
In this case, however, the increase in the concentration of coal and petroleum coke brings about markedly increased viscosity to lose the fluidity and, inversely, the decrease in the concentration of coal and petroleum coke brings about decreased transport efficiency and also expenditure for the dehydration process, leading to impracticability.
Moreover, there is a problem in storage because of the change in produced slurry with the lapse of time, that is, early coagulation and sedimentation of carbonaceous fine powder.
As a method for raising the concentration of carbonaceous fine powder in this carbonaceous fine powder-water slurry and yet producing fluidized carbonaceous fine powder-water slurry, the addition of dispersing agent has been proposed.
For example, as a dispersing agent for coal-water slurry, naphthalenesulfonic acid-formaldehyde condensate (Japanese Unexamined Patent Publication No. Sho 62-16893) can be mentioned. As dispersing agent for petroleum coke-water slurry, polyether compound (Japanese Unexamined Patent Publication No. Sho 59-91195) etc. can be mentioned.
All of these however can hardly be said to be sufficient in viscosity-reducing property and storage stability.
Hence, a dispersing agent having high viscosity-reducing effect at lower addition level and high storage stability of slurry is still demanded.
As a result of diligent studies in detail on aromatic aminosulfonic acid type polymers, the inventors have succeeded in the development of a dispersing agent having high viscosity-reducing effect at lower addition level and yet high storage stability of carbonaceous fine powder-water slurry.
Finally, various water-reducing agents are used recently in the mortar constructions, concrete constructions, etc. aiming at the improvement in different physical properties such as improved workability, enhanced strength and durability and decreased cracking property, but high-performance AE water-reducing agent is still demanded.
So far, as the water-reducing agents for cement, salt of sulfonated melamine resin, polycarboxylate, salt of naphthalenesulfonic acid-formaldehyde high-degree condensate, lignin sulfonate, etc. have been utilized. However, with salt of sulfonated melamine resin, the water-reducing effect is low and high level of addition is required and, with polycarboxylate, the water-reducing effect is high, but increased level of addition causes a remarkable retardation of setting resulting in the deficiency of hardening as the case may be. With salt of naphthalenesulfonic acid-formaldehyde high-degree condensate, the water-reducing effect is high, the retardation of setting is low and the air-entraining property is also low, but the decrease in fluidity of mortar and concrete over time is significant. With lignin sulfonate, the water-reducing effect is high, but the air incorporation is high affecting inversely on the physical properties of mortar and concrete. These and others have been problematic points.
In recent, a concrete-admixing agent containing aromatic aminosulfonic acid-phenol-formaldehyde condensate has been developed (Japanese Unexamined Patent Publication No. Hei 1-113419). It is said that this admixing agent improves the consistency of cement composition and decreases the change in fluidity such as the slump loss with the lapse of time. With this, however, further improvements in high amount of residual monomer on condensation etc. are desired as described earlier.
As a result of diligent studies aiming at the decreased residual monomer (aromatic aminosulfonic acid) in aromatic aminosulfonic acid type admixing agent and the further improvement in fluidity of cement compositions without injuring the preventive effect on decrease in fluidity over time by imparting polar group and stericity to the hydrophobic skeleton, the inventors reached the invention.